The dark purple super berries look like grapes, but are smaller with less pulp. They are packed with iron, fibre, vitamin A and B vitamins, as well as amino acids. They are now a popular functional food and supplement consumed all over the world, and believed to support immune function and keep us healthy.
Although not many scientific studies have been conducted into their effects on human health, acai berries are acknowledged as a rich source of antioxidants, and are also believed to have an anti-inflammatory effect.
Dr Sarah Brewer says: ‘While acai berries and their health benefits are relatively new to us, the people of tropical Central and South America have eaten them for many years. Like many other berries, acai berries are a concentrated source of vital vitamins, antioxidants, fibre, amino acids, and iron – all of which have beneficial effects on health. Supplements are a convenient way to get the concentrated antioxidants found in acai.’
What do acai berries do?
Acai berries are packed with antioxidants such as polyphenols, vitamins C and E, and the minerals manganese and selenium, which are all involved with maintaining immunity.
Antioxidants protect our cells from potentially damaging free radicals – unstable oxygen molecules which can damage cells and cause illnesses such as heart disease. Acai berries have a higher antioxidant content than other types of berries, and have been found to have anti-inflammatory effects. They also contain a plant sterol called beta-sitosterol which inhibits the absorption of so-called bad 'LDL' cholesterol. Acai berries also contain 19 of the 22 amino acids; these are needed by the body for building protein, vital for skin, tissue and muscle maintenance.
Metabolic syndrome is a collection of risk factors – high blood pressure, central obesity (a big waist measurement), raised blood sugar levels and elevated cholesterol – which greatly increase the chances of developing heart disease and type 2 diabetes.
One small trial of 10 overweight people given a daily dose of 200g of acai fruit pulp for a month, found their total cholesterol levels and fasting blood glucose and insulin levels reduced. The authors called for more trials to investigate these effects further.
Acai berries have also been investigated for their potential pain-relieving properties. Participants in one study who all had problems with pain – affecting their range of movement, and normal daily living – drank juice containing acai pulp for 12 weeks. At the end of the study, the researchers found participants had significant reductions in pain, and an improved range of movement and ability to carry out daily activities.
Getting acai berries from your diet
Fresh acai berries are not currently available in the UK, because the fruits don't travel well. However, acai berry is available as a supplement and in capsule, dried or a powdered form, which can be added to soups and smoothies.
Acai berries are safe as a supplement, but check before starting on them if you also take regular medication. High doses of berries may affect the results of MRI scans, so always let your doctor know if you have been taking them.
There is currently no UK or EU recommended daily allowance or upper safety limit. Supplements are available in different doses and double strength Acai Berry one-a-day 500mg extract (equivalent to 4,000mg of fresh berries) is one of the highest doses currently available in supplement form in the UK.